Calculation results from model of Fig. 1. Behaviors of recombination resistances (a) R_rac and (b) R_rdc caused by AC small signal perturbation and DC, respectively; dependences of (c) R_rac and (d) C_rac on frequencies at different values of k (namely 1/τ). We do not consider the product of other factor because these product only change the magnitude of R_rac and C_rac without changing the relationship between them and the frequency.